Diesel is cheaper than gas in much of the U.S. right now, so it's time to see what's the best oil-burner on sale, new or used.

We'd put our money on a used Merc 300 turbodiesel (that's a European model crossing the Sahara above). When we all nuke the shit out of each other in WWIII, the only things left will be cockroaches driving Mercedes diesels. Oh, and the aftermarket is huge, but you'll have to buy from Finland.

What is the best diesel car you can buy in America new or used? Remember: NO ENGINE SWAPS.

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